A datalink is a means of transmitting information from one point to another. When the transmission is accomplished using a wireless means, the datalink may also be referred to as a 'radio link' or 'radio modem'.
The helicopter platform offers a very particular set of advantages over its fixed wing counterpart and this has led to its use in a wide variety of operational scenarios where vertical take-off and landing, and often also the ability to hover, is required.
For fixed wing UAVs operating from traditional runways and landing strips, the landing manoeuvre is usually the most challenging and critical stage of any flight.
Global Navigation Satellite System (GNSS) technology is used in UAV systems to measure translational states (position and velocity) both onboard the aircraft and also for the position of the Ground Control Station (GCS).
Since the earliest days of aviation pilots have used a magnetic compass for navigation, using the instrument to show heading information.